Alternative Names upper respiratory infection, URI, common cold, viral pharyngitis, viral URI
Definition A cold is a viral infection that affects the upper airway including the nose, pharynx, throat, airways, and lungs.
What is going on in the body? The common cold is the most common reason that people miss work or school. There are at least 200 different viruses that cause colds. These include rhinoviruses and coronaviruses, and they are different from the viruses that cause the flu. Cold viruses are very contagious. They are airborne and are transmitted when one breathes, coughs, or sneezes. Cold viruses can be spread when a person with a cold sneezes into his or her hand or blows his or her nose and then touches an object. Cold viruses can live for up to 3 hours on a surface such as a doorknob or toy.
What are the signs and symptoms of the infection? Signs and symptoms of a cold include:
What are the causes and risks of the infection? Colds are caused by rhinoviruses and coronaviruses. Children generally have 6 to 8 colds a year, but they may get as many as 12 if they live in a family with school-age children. Adults usually have 2 to 4 colds a year, and individuals over 60 years of age have about 1 cold a year. Adults have fewer colds than children because they have developed immunity to the particular viruses that cause colds.
Under the following conditions, people are more susceptible to getting a cold:
during the winter months, when people are indoors with others and the humidity is lower.
if they have allergies affecting the nose or throat
What can be done to prevent the infection? Good hand washing is the best way to avoid spreading colds from person to person. There are many measures that can help you avoid catching a cold. To reduce the spread of colds, a person with a cold should:
cover his or her mouth with a disposable tissue when sneezing or coughing, and then discard the tissue
avoid touching his or her eyes, nose, or mouth
wash his or her hands frequently, and especially after coughing or sneezing
Healthy individuals should:
avoid close contact with a person who has a cold
try not to handle objects touched by a person with a cold
wash their hands frequently
There is some evidence that vitamin C may help prevent and decrease the severity of colds. Zinc may also help prevent colds and reduce the severity of colds.
How is the infection diagnosed? Often an individual will diagnose a cold without seeing a doctor. If a doctor is seen, he or she will examine the person's head, neck, and lungs. The doctor will also look for signs and symptoms of more serious respiratory illnesses, such as pneumonia or bronchitis.
What are the long-term effects of the infection? Most colds resolve within 7 to 10 days. Some people will develop complications, such as a sinus infection, ear infection, or long-term cough. People who have breathing difficulties or lung conditions, such as asthma, are more likely to develop complications.
What are the risks to others? Most colds are highly contagious. They are transmitted through respiratory secretions. Sneezing and coughing can spread these droplets. The germ can also be passed on when an individual touches his or her nose and then handles an object that another person later touches. The second person can then pick up the germ from the object and transfer it into his or her own respiratory tract by bringing the hand to the face.
What are the treatments for the infection? Colds are generally treated by addressing the person's symptoms. Bed rest and drinking plenty of fluids can help prevent some complications. Antibiotics do not work against the viruses and can reduce the body's ability to fight viruses. Medications such as paracetamol, ibuprofen, or aspirin can help reduce fever and muscle aches. Because of the risk of a serious condition called Reye's syndrome, children should never be given aspirin.
What happens after treatment for the infection? Cold symptoms usually go away completely in 7 to 10 days. Some adults and children may have secondary ear infections or sinus infections.
How is the infection monitored? Cold symptoms usually clear up within 7 to 10 days. Any new or worsening symptoms should be reported to the doctor.
Author: Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
